Distal protection apparatus with improved wall apposition
In accordance with the present invention, a distal protection and embolic material retrieval device with improved apposition to both large and small vessel walls of varying geometries for enhancing the filtering of embolic material during intravascular procedures while allowing for the passage of blood is provided. The device includes a filter basket designed to maximize apposition of the filtering portion to that of the vessel wall and may include struts which provide circumferential support to the filtering membrane and thereby minimizing or eliminating in-folding of the filter basket. Thin film materials may also be utilized for the filtering membrane of the filter basket. In addition one can incorporate biological and/or pharmaceutical agents in combination with the present invention.
1 . A vascular filtering device comprising:
a compliant substantially enclosed filter membrane having a proximal opening;
a closure ring having a concentric though hole adapted to slidably engage with a guide wire; and
a primary supporting strut having a proximal terminal end, a distal terminal end, and a substantially circumferential intermediate portion between the terminal ends wherein the terminal ends are operatively attached to said closure ring and the circumferential intermediate portion of said supporting strut is operatively attached to the proximal opening of said filter membrane.
2 . The filtering device of claim 1 further comprising one or more additional supporting struts each having a proximal terminal end and a distal terminal end, and a substantially circumferential intermediate portion between the terminal ends spaced apart from said primary supporting strut wherein the proximal opening of said membrane is attached to the circumferential intermediate portion of each of said additional supporting struts and wherein the terminal ends of each of said additional supporting struts is operatively attached to said closure ring.
3 . The filtering device as in claim 1 wherein said membrane is a polymeric film.
4 . The filtering device as in claim 3 wherein said polymeric film is polyurethane having at least one through hole.
5 . The filtering device as in claim 1 wherein said membrane is a Nickel-Titanium Alloy thin film having at least one through hole.
6 . The filtering device of claim 2 wherein the proximal opening of said membrane is scalloped.
7 . The filtering device of claim 2 further comprising:
a supporting collar having a concentric though hole adapted to slidably engage with a guide wire; and
an axial supporting strut having a proximal end and a distal end wherein the distal end of said axial supporting strut is operatively attached to said supporting collar and the proximal end of said axial supporting strut is operatively attached to said closure ring.
8 . The filtering device of claim 6 wherein the scalloped portion of the proximal opening of said membrane substantially follows the circumferential portion of said supporting struts.
9 . The filtering device of claim 6 wherein the scalloped portion of the proximal opening of said membrane is located and extending between adjacent circumferential portions of said supporting struts.
10 . The filtering device of claim 1 wherein said strut is metal.
11 . The filtering device of claim 2 wherein said struts are metal.
12 . The filtering device of claim 1 wherein said membrane incorporates an active compound.
13 . The filtering device of claim 2 wherein said membrane incorporates an active compound.
14 . The filtering device of claim 1 wherein said strut incorporates an active compound.
15 . The filtering device of claim 2 wherein said struts incorporate an active compound.
16 . The filtering device of claim 7 wherein said struts incorporate an active compound.
17 . The filtering device of claim 1 wherein said strut is polymeric.
18 . The filtering device of claim 1 wherein said strut is ceramic.
19 . The filtering device of claim 2 wherein said strut is polymeric.
20 . The filtering device of claim 2 wherein said strut is ceramic.
21 . The filtering device of claim 10 wherein said metal is a shape-memory alloy.
22 . The filtering device of claim 11 wherein said metal is a shape-memory alloy.
23 . The filtering device of claim 10 wherein said metal is a super-elastic alloy.
24 . The filtering device of claim 11 wherein said metal is a super-elastic alloy.
25 . The filtering device of claim 21 wherein said shape-memory alloy is Nickel-Titanium Alloy.
26 . The filtering device of claim 22 wherein said shape-memory alloy is Nickel-Titanium Alloy.
27 . The filtering device of claim 23 wherein said super-elastic alloy is Nickel-Titanium Alloy.
28 . The filtering device of claim 24 wherein said super-elastic alloy is Nickel-Titanium Alloy.
29 . A method for fabricating a filtering device comprising the steps of:
a. providing a hollow tube;
b. removing material from said tube such that what remains are the proximal support ring and strut members each of which are integrally attached to each other being formed from the same tubular component.
30 . The method of claim 29 wherein said tube is Nickel-Titanium Alloy.
31 . The method of claim 29 wherein said removal of material is performed by laser cutting.
32 . A method for fabricating a filtering device comprising the steps of:
a. providing elongated wire;
b. forming said elongated wire into strut loops; and
c. attaching said strut loops to a support collar.
33 . The method of claim 32 wherein said elongated wire is Nickel-Titanium Alloy.